Simplify SkTypeface::charsToGlyphs API to require UTF32 input

Change-Id: I486713c496c40103eef13fa6068ac4d69e32f606
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/207865
Commit-Queue: Ben Wagner <bungeman@google.com>
Reviewed-by: Ben Wagner <bungeman@google.com>
diff --git a/bench/CmapBench.cpp b/bench/CmapBench.cpp
index 3b90e35..cc34af1 100644
--- a/bench/CmapBench.cpp
+++ b/bench/CmapBench.cpp
@@ -44,7 +44,7 @@
 
     SkTypeface* face = r.fFont.getTypefaceOrDefault();
     for (int i = 0; i < r.fLoops; ++i) {
-        face->charsToGlyphs(r.fText, SkTypeface::kUTF32_Encoding, glyphs, r.fCount);
+        face->unicharsToGlyphs(r.fText, r.fCount, glyphs);
     }
 }
 
diff --git a/bench/TypefaceBench.cpp b/bench/TypefaceBench.cpp
index cce5cdb..00b19d2 100644
--- a/bench/TypefaceBench.cpp
+++ b/bench/TypefaceBench.cpp
@@ -8,7 +8,7 @@
 #include <vector>
 
 #include "Benchmark.h"
-#include "SkFontTypes.h"
+#include "SkFont.h"
 #include "SkMakeUnique.h"
 #include "SkTypeface.h"
 #include "SkUTF.h"
@@ -238,12 +238,12 @@
     }
 
     void onDraw(int loops, SkCanvas* canvas) override {
+        SkFont font(fTypeface);
         // Do more loops to reduce variance.
         for (int i = 0; i < loops * 3; ++i) {
             for (auto& line : fLines) {
-                fTypeface->charsToGlyphs(line->utf.data(),
-                                  (SkTypeface::Encoding)fEncoding, fGlyphIds.data(),
-                                  line->glyphCount);
+                font.textToGlyphs(line->utf.data(), line->utf.size(), fEncoding,
+                                  fGlyphIds.data(), line->glyphCount);
             }
         }
     }
diff --git a/gm/atlastext.cpp b/gm/atlastext.cpp
index 328f398..1584ea4 100644
--- a/gm/atlastext.cpp
+++ b/gm/atlastext.cpp
@@ -33,12 +33,14 @@
     auto atlas_font = SkAtlasTextFont::Make(typeface, size);
     int cnt = SkUTF::CountUTF8(text.c_str(), text.size());
     std::unique_ptr<SkGlyphID[]> glyphs(new SkGlyphID[cnt]);
-    typeface->charsToGlyphs(text.c_str(), SkTypeface::Encoding::kUTF8_Encoding, glyphs.get(), cnt);
 
     // Using a paint to get the positions for each glyph.
     SkFont font;
     font.setSize(size);
     font.setTypeface(std::move(typeface));
+
+    font.textToGlyphs(text.c_str(), text.size(), SkTextEncoding::kUTF8, glyphs.get(), cnt);
+
     std::unique_ptr<SkScalar[]> widths(new SkScalar[cnt]);
     font.getWidths(glyphs.get(), cnt, widths.get());
 
diff --git a/include/core/SkFont.h b/include/core/SkFont.h
index 74b7df5..a64c4bb 100644
--- a/include/core/SkFont.h
+++ b/include/core/SkFont.h
@@ -302,6 +302,8 @@
     */
     SkGlyphID unicharToGlyph(SkUnichar uni) const;
 
+    void unicharsToGlyphs(const SkUnichar uni[], int count, SkGlyphID glyphs[]) const;
+
     /** Returns number of glyphs represented by text.
 
         If encoding is kUTF8_SkTextEncoding, kUTF16_SkTextEncoding, or
diff --git a/include/core/SkFontTypes.h b/include/core/SkFontTypes.h
index bb1b03f..6796451 100644
--- a/include/core/SkFontTypes.h
+++ b/include/core/SkFontTypes.h
@@ -9,8 +9,6 @@
 #define SkFontTypes_DEFINED
 
 #include "SkTypes.h"
-// remove me once google3 uses IWYU
-#include "SkTypeface.h"
 
 enum class SkTextEncoding {
     kUTF8,      //!< uses bytes to represent UTF-8 or ASCII
@@ -36,4 +34,7 @@
 #define kNormal_SkFontHinting   SkFontHinting::kNormal
 #define kFull_SkFontHinting     SkFontHinting::kFull
 
+// remove me once google3 uses IWYU
+#include "SkTypeface.h"
+
 #endif
diff --git a/include/core/SkTypeface.h b/include/core/SkTypeface.h
index 7f5af8c..1fba06c 100644
--- a/include/core/SkTypeface.h
+++ b/include/core/SkTypeface.h
@@ -14,6 +14,7 @@
 #include "SkFontArguments.h"
 #include "SkFontParameters.h"
 #include "SkFontStyle.h"
+#include "SkFontTypes.h"
 #include "SkRect.h"
 #include "SkString.h"
 
@@ -176,36 +177,20 @@
      */
     static sk_sp<SkTypeface> MakeDeserialize(SkStream*);
 
-    enum Encoding : uint8_t {
-        kUTF8_Encoding,
-        kUTF16_Encoding,
-        kUTF32_Encoding
-    };
-
     /**
-     *  Given an array of character codes, of the specified encoding,
-     *  optionally return their corresponding glyph IDs (if glyphs is not NULL).
+     *  Given an array of UTF32 character codes, return their corresponding glyph IDs.
      *
-     *  @param chars pointer to the array of character codes
-     *  @param encoding how the characters are encoded
-     *  @param glyphs (optional) returns the corresponding glyph IDs for each
-     *          character code, up to glyphCount values. If a character code is
-     *          not found in the typeface, the corresponding glyph ID will be 0.
-     *  @param glyphCount number of code points in 'chars' to process. If glyphs
-     *          is not NULL, then it must point sufficient memory to write
-     *          glyphCount values into it.
-     *  @return the number of number of continuous non-zero glyph IDs computed
-     *          from the beginning of chars. This value is valid, even if the
-     *          glyphs parameter is NULL.
+     *  @param chars pointer to the array of UTF32 chars
+     *  @param number of chars and glyphs
+     *  @param glyphs returns the corresponding glyph IDs for each character.
      */
-    int charsToGlyphs(const void* chars, Encoding encoding, SkGlyphID glyphs[],
-                      int glyphCount) const;
+    void unicharsToGlyphs(const SkUnichar uni[], int count, SkGlyphID glyphs[]) const;
 
     /**
      *  Return the glyphID that corresponds to the specified unicode code-point
      *  (in UTF32 encoding). If the unichar is not supported, returns 0.
      *
-     *  This is a short-cut for calling charsToGlyphs() with kUTF32_Encoding for one code-point.
+     *  This is a short-cut for calling unicharsToGlyphs().
      */
     SkGlyphID unicharToGlyph(SkUnichar unichar) const;
 
@@ -393,8 +378,7 @@
 
     virtual void onGetFontDescriptor(SkFontDescriptor*, bool* isLocal) const = 0;
 
-    virtual int onCharsToGlyphs(const void* chars, Encoding, SkGlyphID glyphs[],
-                                int glyphCount) const = 0;
+    virtual void onCharsToGlyphs(const SkUnichar* chars, int count, SkGlyphID glyphs[]) const = 0;
     virtual int onCountGlyphs() const = 0;
 
     virtual int onGetUPEM() const = 0;
diff --git a/src/core/SkFont.cpp b/src/core/SkFont.cpp
index 5ab8447..29c8229 100644
--- a/src/core/SkFont.cpp
+++ b/src/core/SkFont.cpp
@@ -170,6 +170,46 @@
     return this->getTypefaceOrDefault()->unicharToGlyph(uni);
 }
 
+void SkFont::unicharsToGlyphs(const SkUnichar uni[], int count, SkGlyphID glyphs[]) const {
+    this->getTypefaceOrDefault()->unicharsToGlyphs(uni, count, glyphs);
+}
+
+class SkConvertToUTF32 {
+public:
+    SkConvertToUTF32() {}
+
+    const SkUnichar* convert(const void* text, size_t byteLength, SkTextEncoding encoding) {
+        const SkUnichar* uni;
+        switch (encoding) {
+            case SkTextEncoding::kUTF8: {
+                uni = fStorage.reset(byteLength);
+                const char* ptr = (const char*)text;
+                const char* end = ptr + byteLength;
+                for (int i = 0; ptr < end; ++i) {
+                    fStorage[i] = SkUTF::NextUTF8(&ptr, end);
+                }
+            } break;
+            case SkTextEncoding::kUTF16: {
+                uni = fStorage.reset(byteLength);
+                const uint16_t* ptr = (const uint16_t*)text;
+                const uint16_t* end = ptr + (byteLength >> 1);
+                for (int i = 0; ptr < end; ++i) {
+                    fStorage[i] = SkUTF::NextUTF16(&ptr, end);
+                }
+            } break;
+            case SkTextEncoding::kUTF32:
+                uni = (const SkUnichar*)text;
+                break;
+            default:
+                SK_ABORT("unexpected enum");
+        }
+        return uni;
+    }
+
+private:
+    SkAutoSTMalloc<256, SkUnichar> fStorage;
+};
+
 int SkFont::textToGlyphs(const void* text, size_t byteLength, SkTextEncoding encoding,
                          SkGlyphID glyphs[], int maxGlyphCount) const {
     if (0 == byteLength) {
@@ -183,26 +223,15 @@
         return count;
     }
 
-    // TODO: unify/eliminate SkTypeface::Encoding with SkTextEncoding
-    SkTypeface::Encoding typefaceEncoding;
-    switch (encoding) {
-        case kUTF8_SkTextEncoding:
-            typefaceEncoding = SkTypeface::kUTF8_Encoding;
-            break;
-        case kUTF16_SkTextEncoding:
-            typefaceEncoding = SkTypeface::kUTF16_Encoding;
-            break;
-        case kUTF32_SkTextEncoding:
-            typefaceEncoding = SkTypeface::kUTF32_Encoding;
-            break;
-        default:
-            SkASSERT(kGlyphID_SkTextEncoding == encoding);
-            // we can early exit, since we already have glyphIDs
-            memcpy(glyphs, text, count << 1);
-            return count;
+    if (encoding == SkTextEncoding::kGlyphID) {
+        memcpy(glyphs, text, count << 1);
+        return count;
     }
 
-    (void) this->getTypefaceOrDefault()->charsToGlyphs(text, typefaceEncoding, glyphs,count);
+    SkConvertToUTF32 storage;
+    const SkUnichar* uni = storage.convert(text, byteLength, encoding);
+
+    this->getTypefaceOrDefault()->unicharsToGlyphs(uni, count, glyphs);
     return count;
 }
 
diff --git a/src/core/SkTypeface.cpp b/src/core/SkTypeface.cpp
index 3950e5d..7786b78 100644
--- a/src/core/SkTypeface.cpp
+++ b/src/core/SkTypeface.cpp
@@ -57,12 +57,8 @@
         return nullptr;
     }
     void onGetFontDescriptor(SkFontDescriptor*, bool*) const override { }
-    virtual int onCharsToGlyphs(const void* chars, Encoding encoding,
-                                uint16_t glyphs[], int glyphCount) const override {
-        if (glyphs && glyphCount > 0) {
-            sk_bzero(glyphs, glyphCount * sizeof(glyphs[0]));
-        }
-        return 0;
+    void onCharsToGlyphs(const SkUnichar* chars, int count, SkGlyphID glyphs[]) const override {
+        sk_bzero(glyphs, count * sizeof(glyphs[0]));
     }
     int onCountGlyphs() const override { return 0; }
     int onGetUPEM() const override { return 0; }
@@ -285,23 +281,16 @@
     return skstd::make_unique<SkFontData>(std::move(stream), index, nullptr, 0);
 };
 
-int SkTypeface::charsToGlyphs(const void* chars, Encoding encoding,
-                              uint16_t glyphs[], int glyphCount) const {
-    if (glyphCount <= 0) {
-        return 0;
+void SkTypeface::unicharsToGlyphs(const SkUnichar uni[], int count, SkGlyphID glyphs[]) const {
+    if (count > 0 && glyphs && uni) {
+        this->onCharsToGlyphs(uni, count, glyphs);
     }
-    if (nullptr == chars || (unsigned)encoding > kUTF32_Encoding) {
-        if (glyphs) {
-            sk_bzero(glyphs, glyphCount * sizeof(glyphs[0]));
-        }
-        return 0;
-    }
-    return this->onCharsToGlyphs(chars, encoding, glyphs, glyphCount);
 }
 
 SkGlyphID SkTypeface::unicharToGlyph(SkUnichar uni) const {
-    SkGlyphID glyphs[1];
-    return this->onCharsToGlyphs(&uni, kUTF32_Encoding, glyphs, 1) == 1 ? glyphs[0] : 0;
+    SkGlyphID glyphs[1] = { 0 };
+    this->onCharsToGlyphs(&uni, 1, glyphs);
+    return glyphs[0];
 }
 
 int SkTypeface::countGlyphs() const {
diff --git a/src/core/SkTypeface_remote.h b/src/core/SkTypeface_remote.h
index 46908c5..dde0ff5 100644
--- a/src/core/SkTypeface_remote.h
+++ b/src/core/SkTypeface_remote.h
@@ -122,10 +122,8 @@
         SK_ABORT("Should never be called.");
         return nullptr;
     }
-    int onCharsToGlyphs(const void* chars, Encoding,
-                        uint16_t glyphs[], int glyphCount) const override {
+    void onCharsToGlyphs(const SkUnichar* chars, int count, SkGlyphID glyphs[]) const override {
         SK_ABORT("Should never be called.");
-        return 0;
     }
     int onCountGlyphs() const override {
         return this->glyphCount();
diff --git a/src/core/SkUtils.h b/src/core/SkUtils.h
index cfbdaae..1597c98 100644
--- a/src/core/SkUtils.h
+++ b/src/core/SkUtils.h
@@ -9,7 +9,7 @@
 #define SkUtils_DEFINED
 
 #include "SkOpts.h"
-#include "SkTypeface.h"
+#include "SkFontTypes.h"
 #include "../utils/SkUTF.h"
 
 /** Similar to memset(), but it assigns a 16, 32, or 64-bit value into the buffer.
@@ -42,23 +42,22 @@
 
 ///////////////////////////////////////////////////////////////////////////////
 
-static inline int SkUTFN_CountUnichars(SkTypeface::Encoding enc, const void* utfN, size_t bytes) {
+static inline int SkUTFN_CountUnichars(SkTextEncoding enc, const void* utfN, size_t bytes) {
     switch (enc) {
-        case SkTypeface::kUTF8_Encoding:  return SkUTF::CountUTF8((const char*)utfN, bytes);
-        case SkTypeface::kUTF16_Encoding: return SkUTF::CountUTF16((const uint16_t*)utfN, bytes);
-        case SkTypeface::kUTF32_Encoding: return SkUTF::CountUTF32((const int32_t*)utfN, bytes);
+        case SkTextEncoding::kUTF8:  return SkUTF::CountUTF8((const char*)utfN, bytes);
+        case SkTextEncoding::kUTF16: return SkUTF::CountUTF16((const uint16_t*)utfN, bytes);
+        case SkTextEncoding::kUTF32: return SkUTF::CountUTF32((const int32_t*)utfN, bytes);
         default: SkDEBUGFAIL("unknown text encoding"); return -1;
     }
 }
 
-static inline SkUnichar SkUTFN_Next(SkTypeface::Encoding enc,
-                                    const void** ptr, const void* stop) {
+static inline SkUnichar SkUTFN_Next(SkTextEncoding enc, const void** ptr, const void* stop) {
     switch (enc) {
-        case SkTypeface::kUTF8_Encoding:
+        case SkTextEncoding::kUTF8:
             return SkUTF::NextUTF8((const char**)ptr, (const char*)stop);
-        case SkTypeface::kUTF16_Encoding:
+        case SkTextEncoding::kUTF16:
             return SkUTF::NextUTF16((const uint16_t**)ptr, (const uint16_t*)stop);
-        case SkTypeface::kUTF32_Encoding:
+        case SkTextEncoding::kUTF32:
             return SkUTF::NextUTF32((const int32_t**)ptr, (const int32_t*)stop);
         default: SkDEBUGFAIL("unknown text encoding"); return -1;
     }
diff --git a/src/ports/SkFontHost_FreeType.cpp b/src/ports/SkFontHost_FreeType.cpp
index c21f884..dd0b800 100644
--- a/src/ports/SkFontHost_FreeType.cpp
+++ b/src/ports/SkFontHost_FreeType.cpp
@@ -1551,62 +1551,17 @@
 
 #include "SkUtils.h"
 
-static SkUnichar next_utf8(const void** chars) {
-    return SkUTF8_NextUnichar((const char**)chars);
-}
-
-static SkUnichar next_utf16(const void** chars) {
-    return SkUTF16_NextUnichar((const uint16_t**)chars);
-}
-
-static SkUnichar next_utf32(const void** chars) {
-    const SkUnichar** uniChars = (const SkUnichar**)chars;
-    SkUnichar uni = **uniChars;
-    *uniChars += 1;
-    return uni;
-}
-
-typedef SkUnichar (*EncodingProc)(const void**);
-
-static EncodingProc find_encoding_proc(SkTypeface::Encoding enc) {
-    static const EncodingProc gProcs[] = {
-        next_utf8, next_utf16, next_utf32
-    };
-    SkASSERT((size_t)enc < SK_ARRAY_COUNT(gProcs));
-    return gProcs[enc];
-}
-
-int SkTypeface_FreeType::onCharsToGlyphs(const void* chars, Encoding encoding,
-                                         uint16_t glyphs[], int glyphCount) const
-{
+void SkTypeface_FreeType::onCharsToGlyphs(const SkUnichar uni[], int count,
+                                          SkGlyphID glyphs[]) const {
     AutoFTAccess fta(this);
     FT_Face face = fta.face();
     if (!face) {
-        if (glyphs) {
-            sk_bzero(glyphs, glyphCount * sizeof(glyphs[0]));
-        }
-        return 0;
+        sk_bzero(glyphs, count * sizeof(glyphs[0]));
+        return;
     }
 
-    EncodingProc next_uni_proc = find_encoding_proc(encoding);
-
-    if (nullptr == glyphs) {
-        for (int i = 0; i < glyphCount; ++i) {
-            if (0 == FT_Get_Char_Index(face, next_uni_proc(&chars))) {
-                return i;
-            }
-        }
-        return glyphCount;
-    } else {
-        int first = glyphCount;
-        for (int i = 0; i < glyphCount; ++i) {
-            unsigned id = FT_Get_Char_Index(face, next_uni_proc(&chars));
-            glyphs[i] = SkToU16(id);
-            if (0 == id && i < first) {
-                first = i;
-            }
-        }
-        return first;
+    for (int i = 0; i < count; ++i) {
+        glyphs[i] = SkToU16(FT_Get_Char_Index(face, uni[i]));
     }
 }
 
diff --git a/src/ports/SkFontHost_FreeType_common.h b/src/ports/SkFontHost_FreeType_common.h
index 02cdb60..064b1a8 100644
--- a/src/ports/SkFontHost_FreeType_common.h
+++ b/src/ports/SkFontHost_FreeType_common.h
@@ -102,8 +102,7 @@
     int onGetUPEM() const override;
     bool onGetKerningPairAdjustments(const uint16_t glyphs[], int count,
                                      int32_t adjustments[]) const override;
-    int onCharsToGlyphs(const void* chars, Encoding, uint16_t glyphs[],
-                        int glyphCount) const override;
+    void onCharsToGlyphs(const SkUnichar uni[], int count, SkGlyphID glyphs[]) const override;
     int onCountGlyphs() const override;
 
     LocalizedStrings* onCreateFamilyNameIterator() const override;
diff --git a/src/ports/SkFontHost_mac.cpp b/src/ports/SkFontHost_mac.cpp
index 5f9cbcf..870ee30 100644
--- a/src/ports/SkFontHost_mac.cpp
+++ b/src/ports/SkFontHost_mac.cpp
@@ -742,8 +742,7 @@
     void onGetFontDescriptor(SkFontDescriptor*, bool*) const override;
     void getGlyphToUnicodeMap(SkUnichar*) const override;
     std::unique_ptr<SkAdvancedTypefaceMetrics> onGetAdvancedMetrics() const override;
-    int onCharsToGlyphs(const void* chars, Encoding,
-                        uint16_t glyphs[], int glyphCount) const override;
+    void onCharsToGlyphs(const SkUnichar* chars, int count, SkGlyphID glyphs[]) const override;
     int onCountGlyphs() const override;
 
     void* onGetCTFontRef() const override { return (void*)fFontRef.get(); }
@@ -2333,9 +2332,7 @@
     *isLocalStream = fIsFromStream;
 }
 
-int SkTypeface_Mac::onCharsToGlyphs(const void* chars, Encoding encoding,
-                                    uint16_t glyphs[], int glyphCount) const
-{
+void SkTypeface_Mac::onCharsToGlyphs(const SkUnichar uni[], int count, SkGlyphID glyphs[]) const {
     // Undocumented behavior of CTFontGetGlyphsForCharacters with non-bmp code points:
     // When a surrogate pair is detected, the glyph index used is the index of the high surrogate.
     // It is documented that if a mapping is unavailable, the glyph will be set to 0.
@@ -2343,81 +2340,38 @@
     SkAutoSTMalloc<1024, UniChar> charStorage;
     const UniChar* src; // UniChar is a UTF-16 16-bit code unit.
     int srcCount;
-    switch (encoding) {
-        case kUTF8_Encoding: {
-            const char* utf8 = reinterpret_cast<const char*>(chars);
-            UniChar* utf16 = charStorage.reset(2 * glyphCount);
-            src = utf16;
-            for (int i = 0; i < glyphCount; ++i) {
-                SkUnichar uni = SkUTF8_NextUnichar(&utf8);
-                utf16 += SkUTF::ToUTF16(uni, utf16);
-            }
-            srcCount = SkToInt(utf16 - src);
-            break;
-        }
-        case kUTF16_Encoding: {
-            src = reinterpret_cast<const UniChar*>(chars);
-            int extra = 0;
-            for (int i = 0; i < glyphCount; ++i) {
-                if (SkUTF16_IsLeadingSurrogate(src[i + extra])) {
-                    ++extra;
-                }
-            }
-            srcCount = glyphCount + extra;
-            break;
-        }
-        case kUTF32_Encoding: {
-            const SkUnichar* utf32 = reinterpret_cast<const SkUnichar*>(chars);
-            UniChar* utf16 = charStorage.reset(2 * glyphCount);
-            src = utf16;
-            for (int i = 0; i < glyphCount; ++i) {
-                utf16 += SkUTF::ToUTF16(utf32[i], utf16);
-            }
-            srcCount = SkToInt(utf16 - src);
-            break;
-        }
+    const SkUnichar* utf32 = reinterpret_cast<const SkUnichar*>(uni);
+    UniChar* utf16 = charStorage.reset(2 * count);
+    src = utf16;
+    for (int i = 0; i < count; ++i) {
+        utf16 += SkUTF::ToUTF16(utf32[i], utf16);
     }
+    srcCount = SkToInt(utf16 - src);
 
-    // If glyphs is nullptr, CT still needs glyph storage for finding the first failure.
-    // Also, if there are any non-bmp code points, the provided 'glyphs' storage will be inadequate.
+    // If there are any non-bmp code points, the provided 'glyphs' storage will be inadequate.
     SkAutoSTMalloc<1024, uint16_t> glyphStorage;
     uint16_t* macGlyphs = glyphs;
-    if (nullptr == macGlyphs || srcCount > glyphCount) {
+    if (srcCount > count) {
         macGlyphs = glyphStorage.reset(srcCount);
     }
 
-    bool allEncoded = CTFontGetGlyphsForCharacters(fFontRef.get(), src, macGlyphs, srcCount);
+    CTFontGetGlyphsForCharacters(fFontRef.get(), src, macGlyphs, srcCount);
 
     // If there were any non-bmp, then copy and compact.
-    // If 'glyphs' is nullptr, then compact glyphStorage in-place.
-    // If all are bmp and 'glyphs' is non-nullptr, 'glyphs' already contains the compact glyphs.
-    // If some are non-bmp and 'glyphs' is non-nullptr, copy and compact into 'glyphs'.
-    uint16_t* compactedGlyphs = glyphs;
-    if (nullptr == compactedGlyphs) {
-        compactedGlyphs = macGlyphs;
-    }
-    if (srcCount > glyphCount) {
+    // If all are bmp, 'glyphs' already contains the compact glyphs.
+    // If some are non-bmp, copy and compact into 'glyphs'.
+    if (srcCount > count) {
+        SkASSERT(glyphs != macGlyphs);
         int extra = 0;
-        for (int i = 0; i < glyphCount; ++i) {
-            compactedGlyphs[i] = macGlyphs[i + extra];
+        for (int i = 0; i < count; ++i) {
+            glyphs[i] = macGlyphs[i + extra];
             if (SkUTF16_IsLeadingSurrogate(src[i + extra])) {
                 ++extra;
             }
         }
+    } else {
+        SkASSERT(glyphs == macGlyphs);
     }
-
-    if (allEncoded) {
-        return glyphCount;
-    }
-
-    // If we got false, then we need to manually look for first failure.
-    for (int i = 0; i < glyphCount; ++i) {
-        if (0 == compactedGlyphs[i]) {
-            return i;
-        }
-    }
-    // Odd to get here, as we expected CT to have returned true up front.
-    return glyphCount;
 }
 
 int SkTypeface_Mac::onCountGlyphs() const {
diff --git a/src/ports/SkFontHost_win.cpp b/src/ports/SkFontHost_win.cpp
index bbb37c7..bb76fc5 100644
--- a/src/ports/SkFontHost_win.cpp
+++ b/src/ports/SkFontHost_win.cpp
@@ -267,8 +267,7 @@
     void getGlyphToUnicodeMap(SkUnichar*) const override;
     std::unique_ptr<SkAdvancedTypefaceMetrics> onGetAdvancedMetrics() const override;
     void onGetFontDescriptor(SkFontDescriptor*, bool*) const override;
-    int onCharsToGlyphs(const void* chars, Encoding encoding,
-                        uint16_t glyphs[], int glyphCount) const override;
+    void onCharsToGlyphs(const SkUnichar* chars, int count, SkGlyphID glyphs[]) const override;
     int onCountGlyphs() const override;
     int onGetUPEM() const override;
     void onGetFamilyName(SkString* familyName) const override;
@@ -1917,8 +1916,8 @@
 };
 #define SkAutoHDC(...) SK_REQUIRE_LOCAL_VAR(SkAutoHDC)
 
-int LogFontTypeface::onCharsToGlyphs(const void* chars, Encoding encoding,
-                                     uint16_t userGlyphs[], int glyphCount) const
+void LogFontTypeface::onCharsToGlyphs(const SkUnichar uni[], int glyphCount,
+                                      SkGlyphID glyphs[]) const
 {
     SkAutoHDC hdc(fLogFont);
 
@@ -1931,119 +1930,35 @@
     }
     bool Ox1FHack = !(tm.tmPitchAndFamily & TMPF_VECTOR) /*&& winVer < Vista */;
 
-    SkAutoSTMalloc<256, uint16_t> scratchGlyphs;
-    uint16_t* glyphs;
-    if (userGlyphs != nullptr) {
-        glyphs = userGlyphs;
-    } else {
-        glyphs = scratchGlyphs.reset(glyphCount);
-    }
-
     SCRIPT_CACHE sc = 0;
-    switch (encoding) {
-    case SkTypeface::kUTF8_Encoding: {
-        static const int scratchCount = 256;
-        WCHAR scratch[scratchCount];
-        int glyphIndex = 0;
-        const char* currentUtf8 = reinterpret_cast<const char*>(chars);
-        SkUnichar currentChar = 0;
-        if (glyphCount) {
-            currentChar = SkUTF8_NextUnichar(&currentUtf8);
+    static const int scratchCount = 256;
+    WCHAR scratch[scratchCount];
+    int glyphIndex = 0;
+    const uint32_t* utf32 = reinterpret_cast<const uint32_t*>(uni);
+    while (glyphIndex < glyphCount) {
+        // Try a run of bmp.
+        int glyphsLeft = SkTMin(glyphCount - glyphIndex, scratchCount);
+        int runLength = 0;
+        while (runLength < glyphsLeft && utf32[glyphIndex + runLength] <= 0xFFFF) {
+            scratch[runLength] = static_cast<WCHAR>(utf32[glyphIndex + runLength]);
+            ++runLength;
         }
-        while (glyphIndex < glyphCount) {
-            // Try a run of bmp.
-            int glyphsLeft = SkTMin(glyphCount - glyphIndex, scratchCount);
-            int runLength = 0;
-            while (runLength < glyphsLeft && currentChar <= 0xFFFF) {
-                scratch[runLength] = static_cast<WCHAR>(currentChar);
-                ++runLength;
-                if (runLength < glyphsLeft) {
-                    currentChar = SkUTF8_NextUnichar(&currentUtf8);
-                }
-            }
-            if (runLength) {
-                bmpCharsToGlyphs(hdc, scratch, runLength, &glyphs[glyphIndex], Ox1FHack);
-                glyphIndex += runLength;
-            }
+        if (runLength) {
+            bmpCharsToGlyphs(hdc, scratch, runLength, &glyphs[glyphIndex], Ox1FHack);
+            glyphIndex += runLength;
+        }
 
-            // Try a run of non-bmp.
-            while (glyphIndex < glyphCount && currentChar > 0xFFFF) {
-                SkUTF::ToUTF16(currentChar, reinterpret_cast<uint16_t*>(scratch));
-                glyphs[glyphIndex] = nonBmpCharToGlyph(hdc, &sc, scratch);
-                ++glyphIndex;
-                if (glyphIndex < glyphCount) {
-                    currentChar = SkUTF8_NextUnichar(&currentUtf8);
-                }
-            }
+        // Try a run of non-bmp.
+        while (glyphIndex < glyphCount && utf32[glyphIndex] > 0xFFFF) {
+            SkUTF::ToUTF16(utf32[glyphIndex], reinterpret_cast<uint16_t*>(scratch));
+            glyphs[glyphIndex] = nonBmpCharToGlyph(hdc, &sc, scratch);
+            ++glyphIndex;
         }
-        break;
-    }
-    case SkTypeface::kUTF16_Encoding: {
-        int glyphIndex = 0;
-        const WCHAR* currentUtf16 = reinterpret_cast<const WCHAR*>(chars);
-        while (glyphIndex < glyphCount) {
-            // Try a run of bmp.
-            int glyphsLeft = glyphCount - glyphIndex;
-            int runLength = 0;
-            while (runLength < glyphsLeft && !SkUTF16_IsLeadingSurrogate(currentUtf16[runLength])) {
-                ++runLength;
-            }
-            if (runLength) {
-                bmpCharsToGlyphs(hdc, currentUtf16, runLength, &glyphs[glyphIndex], Ox1FHack);
-                glyphIndex += runLength;
-                currentUtf16 += runLength;
-            }
-
-            // Try a run of non-bmp.
-            while (glyphIndex < glyphCount && SkUTF16_IsLeadingSurrogate(*currentUtf16)) {
-                glyphs[glyphIndex] = nonBmpCharToGlyph(hdc, &sc, currentUtf16);
-                ++glyphIndex;
-                currentUtf16 += 2;
-            }
-        }
-        break;
-    }
-    case SkTypeface::kUTF32_Encoding: {
-        static const int scratchCount = 256;
-        WCHAR scratch[scratchCount];
-        int glyphIndex = 0;
-        const uint32_t* utf32 = reinterpret_cast<const uint32_t*>(chars);
-        while (glyphIndex < glyphCount) {
-            // Try a run of bmp.
-            int glyphsLeft = SkTMin(glyphCount - glyphIndex, scratchCount);
-            int runLength = 0;
-            while (runLength < glyphsLeft && utf32[glyphIndex + runLength] <= 0xFFFF) {
-                scratch[runLength] = static_cast<WCHAR>(utf32[glyphIndex + runLength]);
-                ++runLength;
-            }
-            if (runLength) {
-                bmpCharsToGlyphs(hdc, scratch, runLength, &glyphs[glyphIndex], Ox1FHack);
-                glyphIndex += runLength;
-            }
-
-            // Try a run of non-bmp.
-            while (glyphIndex < glyphCount && utf32[glyphIndex] > 0xFFFF) {
-                SkUTF::ToUTF16(utf32[glyphIndex], reinterpret_cast<uint16_t*>(scratch));
-                glyphs[glyphIndex] = nonBmpCharToGlyph(hdc, &sc, scratch);
-                ++glyphIndex;
-            }
-        }
-        break;
-    }
-    default:
-        SK_ABORT("Invalid Text Encoding");
     }
 
     if (sc) {
         ::ScriptFreeCache(&sc);
     }
-
-    for (int i = 0; i < glyphCount; ++i) {
-        if (0 == glyphs[i]) {
-            return i;
-        }
-    }
-    return glyphCount;
 }
 
 int LogFontTypeface::onCountGlyphs() const {
diff --git a/src/ports/SkTypeface_win_dw.cpp b/src/ports/SkTypeface_win_dw.cpp
index c7802aa..bcb9d7d 100644
--- a/src/ports/SkTypeface_win_dw.cpp
+++ b/src/ports/SkTypeface_win_dw.cpp
@@ -52,78 +52,9 @@
     *isLocalStream = SkToBool(fDWriteFontFileLoader.get());
 }
 
-static SkUnichar next_utf8(const void** chars) {
-    return SkUTF8_NextUnichar((const char**)chars);
-}
-
-static SkUnichar next_utf16(const void** chars) {
-    return SkUTF16_NextUnichar((const uint16_t**)chars);
-}
-
-static SkUnichar next_utf32(const void** chars) {
-    const SkUnichar** uniChars = (const SkUnichar**)chars;
-    SkUnichar uni = **uniChars;
-    *uniChars += 1;
-    return uni;
-}
-
-typedef SkUnichar (*EncodingProc)(const void**);
-
-static EncodingProc find_encoding_proc(SkTypeface::Encoding enc) {
-    static const EncodingProc gProcs[] = {
-        next_utf8, next_utf16, next_utf32
-    };
-    SkASSERT((size_t)enc < SK_ARRAY_COUNT(gProcs));
-    return gProcs[enc];
-}
-
-int DWriteFontTypeface::onCharsToGlyphs(const void* chars, Encoding encoding,
-                                        uint16_t glyphs[], int glyphCount) const
-{
-    if (nullptr == glyphs) {
-        EncodingProc next_ucs4_proc = find_encoding_proc(encoding);
-        for (int i = 0; i < glyphCount; ++i) {
-            const SkUnichar c = next_ucs4_proc(&chars);
-            BOOL exists;
-            fDWriteFont->HasCharacter(c, &exists);
-            if (!exists) {
-                return i;
-            }
-        }
-        return glyphCount;
-    }
-
-    switch (encoding) {
-    case SkTypeface::kUTF8_Encoding:
-    case SkTypeface::kUTF16_Encoding: {
-        static const int scratchCount = 256;
-        UINT32 scratch[scratchCount];
-        EncodingProc next_ucs4_proc = find_encoding_proc(encoding);
-        for (int baseGlyph = 0; baseGlyph < glyphCount; baseGlyph += scratchCount) {
-            int glyphsLeft = glyphCount - baseGlyph;
-            int limit = SkTMin(glyphsLeft, scratchCount);
-            for (int i = 0; i < limit; ++i) {
-                scratch[i] = next_ucs4_proc(&chars);
-            }
-            fDWriteFontFace->GetGlyphIndices(scratch, limit, &glyphs[baseGlyph]);
-        }
-        break;
-    }
-    case SkTypeface::kUTF32_Encoding: {
-        const UINT32* utf32 = reinterpret_cast<const UINT32*>(chars);
-        fDWriteFontFace->GetGlyphIndices(utf32, glyphCount, glyphs);
-        break;
-    }
-    default:
-        SK_ABORT("Invalid Text Encoding");
-    }
-
-    for (int i = 0; i < glyphCount; ++i) {
-        if (0 == glyphs[i]) {
-            return i;
-        }
-    }
-    return glyphCount;
+void DWriteFontTypeface::onCharsToGlyphs(const SkUnichar uni[], int count,
+                                         SkGlyphID glyphs[]) const {
+    fDWriteFontFace->GetGlyphIndices((const UINT32*)uni, count, glyphs);
 }
 
 int DWriteFontTypeface::onCountGlyphs() const {
diff --git a/src/ports/SkTypeface_win_dw.h b/src/ports/SkTypeface_win_dw.h
index 855ef79..0e11333 100644
--- a/src/ports/SkTypeface_win_dw.h
+++ b/src/ports/SkTypeface_win_dw.h
@@ -116,8 +116,7 @@
     void getGlyphToUnicodeMap(SkUnichar* glyphToUnicode) const override;
     std::unique_ptr<SkAdvancedTypefaceMetrics> onGetAdvancedMetrics() const override;
     void onGetFontDescriptor(SkFontDescriptor*, bool*) const override;
-    int onCharsToGlyphs(const void* chars, Encoding encoding,
-                        uint16_t glyphs[], int glyphCount) const override;
+    void onCharsToGlyphs(const SkUnichar* chars, int count, SkGlyphID glyphs[]) const override;
     int onCountGlyphs() const override;
     int onGetUPEM() const override;
     void onGetFamilyName(SkString* familyName) const override;
diff --git a/tests/FontHostTest.cpp b/tests/FontHostTest.cpp
index c9846a6..0b70ac6 100644
--- a/tests/FontHostTest.cpp
+++ b/tests/FontHostTest.cpp
@@ -69,50 +69,6 @@
     }
 }
 
-// The following three are all the same code points in various encodings.
-// a中Яיו𝄞a𠮟
-static uint8_t utf8Chars[] = { 0x61, 0xE4,0xB8,0xAD, 0xD0,0xAF, 0xD7,0x99, 0xD7,0x95, 0xF0,0x9D,0x84,0x9E, 0x61, 0xF0,0xA0,0xAE,0x9F };
-static uint16_t utf16Chars[] = { 0x0061, 0x4E2D, 0x042F, 0x05D9, 0x05D5, 0xD834,0xDD1E, 0x0061, 0xD842,0xDF9F };
-static uint32_t utf32Chars[] = { 0x00000061, 0x00004E2D, 0x0000042F, 0x000005D9, 0x000005D5, 0x0001D11E, 0x00000061, 0x00020B9F };
-
-struct CharsToGlyphs_TestData {
-    const void* chars;
-    int charCount;
-    size_t charsByteLength;
-    SkTypeface::Encoding typefaceEncoding;
-    const char* name;
-} static charsToGlyphs_TestData[] = {
-    { utf8Chars, 8, sizeof(utf8Chars), SkTypeface::kUTF8_Encoding, "Simple UTF-8" },
-    { utf16Chars, 8, sizeof(utf16Chars), SkTypeface::kUTF16_Encoding, "Simple UTF-16" },
-    { utf32Chars, 8, sizeof(utf32Chars), SkTypeface::kUTF32_Encoding, "Simple UTF-32" },
-};
-
-// Test that SkPaint::textToGlyphs agrees with SkTypeface::charsToGlyphs.
-static void test_charsToGlyphs(skiatest::Reporter* reporter, sk_sp<SkTypeface> face) {
-    uint16_t paintGlyphIds[256];
-    uint16_t faceGlyphIds[256];
-
-    for (size_t testIndex = 0; testIndex < SK_ARRAY_COUNT(charsToGlyphs_TestData); ++testIndex) {
-        CharsToGlyphs_TestData& test = charsToGlyphs_TestData[testIndex];
-        SkTextEncoding encoding = static_cast<SkTextEncoding>(test.typefaceEncoding);
-
-        SkFont font(face);
-        font.textToGlyphs(test.chars, test.charsByteLength, encoding,
-                          paintGlyphIds, SK_ARRAY_COUNT(paintGlyphIds));
-
-        face->charsToGlyphs(test.chars, test.typefaceEncoding, faceGlyphIds, test.charCount);
-
-        for (int i = 0; i < test.charCount; ++i) {
-            SkString name;
-            face->getFamilyName(&name);
-            SkString a;
-            a.appendf("%s, paintGlyphIds[%d] = %d, faceGlyphIds[%d] = %d, face = %s",
-                      test.name, i, (int)paintGlyphIds[i], i, (int)faceGlyphIds[i], name.c_str());
-            REPORTER_ASSERT(reporter, paintGlyphIds[i] == faceGlyphIds[i], a.c_str());
-        }
-    }
-}
-
 static void test_fontstream(skiatest::Reporter* reporter, SkStream* stream, int ttcIndex) {
     int n = SkFontStream::GetTableTags(stream, ttcIndex, nullptr);
     SkAutoTArray<SkFontTableTag> array(n);
@@ -230,7 +186,6 @@
             test_tables(reporter, face);
             test_unitsPerEm(reporter, face);
             test_countGlyphs(reporter, face);
-            test_charsToGlyphs(reporter, face);
         }
     }
 }
diff --git a/tests/FontMgrTest.cpp b/tests/FontMgrTest.cpp
index 67867b5..c0d8b49 100644
--- a/tests/FontMgrTest.cpp
+++ b/tests/FontMgrTest.cpp
@@ -136,12 +136,8 @@
             return nullptr;
         }
         void onGetFontDescriptor(SkFontDescriptor*, bool*) const override { }
-        virtual int onCharsToGlyphs(const void* chars, Encoding encoding,
-            uint16_t glyphs[], int glyphCount) const override {
-            if (glyphs && glyphCount > 0) {
-                sk_bzero(glyphs, glyphCount * sizeof(glyphs[0]));
-            }
-            return 0;
+        void onCharsToGlyphs(const SkUnichar* chars, int count, SkGlyphID glyphs[]) const override {
+            sk_bzero(glyphs, count * sizeof(glyphs[0]));
         }
         int onCountGlyphs() const override { return 0; }
         int onGetUPEM() const override { return 0; }
diff --git a/tests/PaintTest.cpp b/tests/PaintTest.cpp
index f22aaf5..503bd49 100644
--- a/tests/PaintTest.cpp
+++ b/tests/PaintTest.cpp
@@ -21,90 +21,6 @@
 #include "Test.h"
 #undef ASSERT
 
-static size_t uni_to_utf8(const SkUnichar src[], void* dst, int count) {
-    char* u8 = (char*)dst;
-    for (int i = 0; i < count; ++i) {
-        int n = SkToInt(SkUTF::ToUTF8(src[i], u8));
-        u8 += n;
-    }
-    return u8 - (char*)dst;
-}
-
-static size_t uni_to_utf16(const SkUnichar src[], void* dst, int count) {
-    uint16_t* u16 = (uint16_t*)dst;
-    for (int i = 0; i < count; ++i) {
-        int n = SkToInt(SkUTF::ToUTF16(src[i], u16));
-        u16 += n;
-    }
-    return (char*)u16 - (char*)dst;
-}
-
-static size_t uni_to_utf32(const SkUnichar src[], void* dst, int count) {
-    SkUnichar* u32 = (SkUnichar*)dst;
-    if (src != u32) {
-        memcpy(u32, src, count * sizeof(SkUnichar));
-    }
-    return count * sizeof(SkUnichar);
-}
-
-static int find_first_zero(const uint16_t glyphs[], int count) {
-    for (int i = 0; i < count; ++i) {
-        if (0 == glyphs[i]) {
-            return i;
-        }
-    }
-    return count;
-}
-
-DEF_TEST(Paint_cmap, reporter) {
-    // need to implement charsToGlyphs on other backends (e.g. linux, win)
-    // before we can run this tests everywhere
-    return;
-
-    static const int NGLYPHS = 64;
-
-    SkUnichar src[NGLYPHS];
-    SkUnichar dst[NGLYPHS]; // used for utf8, utf16, utf32 storage
-
-    static const struct {
-        size_t (*fSeedTextProc)(const SkUnichar[], void* dst, int count);
-        SkTextEncoding   fEncoding;
-    } gRec[] = {
-        { uni_to_utf8,  kUTF8_SkTextEncoding },
-        { uni_to_utf16, kUTF16_SkTextEncoding },
-        { uni_to_utf32, kUTF32_SkTextEncoding },
-    };
-
-    SkRandom rand;
-    SkFont font;
-    font.setTypeface(SkTypeface::MakeDefault());
-    SkTypeface* face = font.getTypefaceOrDefault();
-
-    for (int i = 0; i < 1000; ++i) {
-        // generate some random text
-        for (int j = 0; j < NGLYPHS; ++j) {
-            src[j] = ' ' + j;
-        }
-        // inject some random chars, to sometimes abort early
-        src[rand.nextU() & 63] = rand.nextU() & 0xFFF;
-
-        for (size_t k = 0; k < SK_ARRAY_COUNT(gRec); ++k) {
-            size_t len = gRec[k].fSeedTextProc(src, dst, NGLYPHS);
-
-            uint16_t    glyphs0[NGLYPHS], glyphs1[NGLYPHS];
-
-            int nglyphs = font.textToGlyphs(dst, len, gRec[k].fEncoding, glyphs0, NGLYPHS);
-            int first = face->charsToGlyphs(dst, (SkTypeface::Encoding)gRec[k].fEncoding,
-                                            glyphs1, NGLYPHS);
-            int index = find_first_zero(glyphs1, NGLYPHS);
-
-            REPORTER_ASSERT(reporter, NGLYPHS == nglyphs);
-            REPORTER_ASSERT(reporter, index == first);
-            REPORTER_ASSERT(reporter, 0 == memcmp(glyphs0, glyphs1, NGLYPHS * sizeof(uint16_t)));
-        }
-    }
-}
-
 // temparary api for bicubic, just be sure we can set/clear it
 DEF_TEST(Paint_filterQuality, reporter) {
     SkPaint p0, p1;
diff --git a/tests/SkRemoteGlyphCacheTest.cpp b/tests/SkRemoteGlyphCacheTest.cpp
index 07cad45..7e6cdec 100644
--- a/tests/SkRemoteGlyphCacheTest.cpp
+++ b/tests/SkRemoteGlyphCacheTest.cpp
@@ -496,7 +496,8 @@
     SkASSERT(runBuffer.utf8text == nullptr);
     SkASSERT(runBuffer.clusters == nullptr);
 
-    glyphTf->charsToGlyphs(s, SkTypeface::kUTF8_Encoding, runBuffer.glyphs, runSize);
+    SkFont(sk_ref_sp(glyphTf)).textToGlyphs(s, strlen(s), SkTextEncoding::kUTF8,
+                                            runBuffer.glyphs, runSize);
 
     SkRect glyphBounds;
     font.getWidths(runBuffer.glyphs, 1, nullptr, &glyphBounds);
diff --git a/tools/fonts/RandomScalerContext.cpp b/tools/fonts/RandomScalerContext.cpp
index 3431c93..d20bf2b 100644
--- a/tools/fonts/RandomScalerContext.cpp
+++ b/tools/fonts/RandomScalerContext.cpp
@@ -182,11 +182,8 @@
     fProxy->getFontDescriptor(desc, isLocal);
 }
 
-int SkRandomTypeface::onCharsToGlyphs(const void* chars,
-                                      Encoding    encoding,
-                                      uint16_t    glyphs[],
-                                      int         glyphCount) const {
-    return fProxy->charsToGlyphs(chars, encoding, glyphs, glyphCount);
+void SkRandomTypeface::onCharsToGlyphs(const SkUnichar* uni, int count, SkGlyphID glyphs[]) const {
+    fProxy->unicharsToGlyphs(uni, count, glyphs);
 }
 
 int SkRandomTypeface::onCountGlyphs() const { return fProxy->countGlyphs(); }
diff --git a/tools/fonts/RandomScalerContext.h b/tools/fonts/RandomScalerContext.h
index ea1b655..d0eb02c 100644
--- a/tools/fonts/RandomScalerContext.h
+++ b/tools/fonts/RandomScalerContext.h
@@ -33,10 +33,7 @@
     sk_sp<SkTypeface> onMakeClone(const SkFontArguments& args) const override;
     void              onGetFontDescriptor(SkFontDescriptor*, bool* isLocal) const override;
 
-    int onCharsToGlyphs(const void* chars,
-                        Encoding    encoding,
-                        uint16_t    glyphs[],
-                        int         glyphCount) const override;
+    void onCharsToGlyphs(const SkUnichar* chars, int count, SkGlyphID glyphs[]) const override;
     int onCountGlyphs() const override;
     int onGetUPEM() const override;
 
diff --git a/tools/fonts/TestEmptyTypeface.h b/tools/fonts/TestEmptyTypeface.h
index bd630d3..dc358a7 100644
--- a/tools/fonts/TestEmptyTypeface.h
+++ b/tools/fonts/TestEmptyTypeface.h
@@ -30,14 +30,8 @@
         return nullptr;
     }
     void        onGetFontDescriptor(SkFontDescriptor*, bool*) const override {}
-    virtual int onCharsToGlyphs(const void* chars,
-                                Encoding    encoding,
-                                uint16_t    glyphs[],
-                                int         glyphCount) const override {
-        if (glyphs && glyphCount > 0) {
-            sk_bzero(glyphs, glyphCount * sizeof(glyphs[0]));
-        }
-        return 0;
+    void onCharsToGlyphs(const SkUnichar* chars, int count, SkGlyphID glyphs[]) const override {
+        sk_bzero(glyphs, count * sizeof(glyphs[0]));
     }
     int onCountGlyphs() const override { return 0; }
     int onGetUPEM() const override { return 0; }
diff --git a/tools/fonts/TestSVGTypeface.cpp b/tools/fonts/TestSVGTypeface.cpp
index 80ee05a..e180f96 100644
--- a/tools/fonts/TestSVGTypeface.cpp
+++ b/tools/fonts/TestSVGTypeface.cpp
@@ -150,27 +150,11 @@
     *isLocal = false;
 }
 
-int TestSVGTypeface::onCharsToGlyphs(const void* chars,
-                                     Encoding    encoding,
-                                     uint16_t    glyphs[],
-                                     int         glyphCount) const {
-    auto utf8  = (const char*)chars;
-    auto utf16 = (const uint16_t*)chars;
-    auto utf32 = (const SkUnichar*)chars;
-
-    for (int i = 0; i < glyphCount; i++) {
-        SkUnichar ch;
-        switch (encoding) {
-            case kUTF8_Encoding: ch = SkUTF8_NextUnichar(&utf8); break;
-            case kUTF16_Encoding: ch = SkUTF16_NextUnichar(&utf16); break;
-            case kUTF32_Encoding: ch = *utf32++; break;
-        }
-        if (glyphs) {
-            SkGlyphID* g = fCMap.find(ch);
-            glyphs[i]    = g ? *g : 0;
-        }
+void TestSVGTypeface::onCharsToGlyphs(const SkUnichar uni[], int count, SkGlyphID glyphs[]) const {
+    for (int i = 0; i < count; i++) {
+        SkGlyphID* g = fCMap.find(uni[i]);
+        glyphs[i]    = g ? *g : 0;
     }
-    return glyphCount;
 }
 
 void TestSVGTypeface::onGetFamilyName(SkString* familyName) const { *familyName = fName; }
diff --git a/tools/fonts/TestSVGTypeface.h b/tools/fonts/TestSVGTypeface.h
index ba0d789..592418a 100644
--- a/tools/fonts/TestSVGTypeface.h
+++ b/tools/fonts/TestSVGTypeface.h
@@ -94,10 +94,7 @@
 
     void onGetFontDescriptor(SkFontDescriptor* desc, bool* isLocal) const override;
 
-    int onCharsToGlyphs(const void* chars,
-                        Encoding    encoding,
-                        uint16_t    glyphs[],
-                        int         glyphCount) const override;
+    void onCharsToGlyphs(const SkUnichar* chars, int count, SkGlyphID glyphs[]) const override;
 
     int onCountGlyphs() const override { return fGlyphCount; }
 
diff --git a/tools/fonts/TestTypeface.cpp b/tools/fonts/TestTypeface.cpp
index 05f5d79..4641eef 100644
--- a/tools/fonts/TestTypeface.cpp
+++ b/tools/fonts/TestTypeface.cpp
@@ -132,26 +132,10 @@
     *isLocal = false;
 }
 
-int TestTypeface::onCharsToGlyphs(const void* chars,
-                                  Encoding    encoding,
-                                  SkGlyphID   glyphs[],
-                                  int         glyphCount) const {
-    auto utf8  = (const char*)chars;
-    auto utf16 = (const uint16_t*)chars;
-    auto utf32 = (const SkUnichar*)chars;
-
-    for (int i = 0; i < glyphCount; ++i) {
-        SkUnichar ch;
-        switch (encoding) {
-            case kUTF8_Encoding: ch = SkUTF8_NextUnichar(&utf8); break;
-            case kUTF16_Encoding: ch = SkUTF16_NextUnichar(&utf16); break;
-            case kUTF32_Encoding: ch = *utf32++; break;
-        }
-        if (glyphs) {
-            glyphs[i] = fTestFont->glyphForUnichar(ch);
-        }
+void TestTypeface::onCharsToGlyphs(const SkUnichar uni[], int count, SkGlyphID glyphs[]) const {
+    for (int i = 0; i < count; ++i) {
+        glyphs[i] = fTestFont->glyphForUnichar(uni[i]);
     }
-    return glyphCount;
 }
 
 void TestTypeface::onGetFamilyName(SkString* familyName) const { *familyName = fTestFont->fName; }
diff --git a/tools/fonts/TestTypeface.h b/tools/fonts/TestTypeface.h
index 8ea837f..7dcd574 100644
--- a/tools/fonts/TestTypeface.h
+++ b/tools/fonts/TestTypeface.h
@@ -83,10 +83,7 @@
 
     void onGetFontDescriptor(SkFontDescriptor* desc, bool* isLocal) const override;
 
-    int onCharsToGlyphs(const void* chars,
-                        Encoding    encoding,
-                        uint16_t    glyphs[],
-                        int         glyphCount) const override;
+    void onCharsToGlyphs(const SkUnichar* chars, int count, SkGlyphID glyphs[]) const override;
 
     int onCountGlyphs() const override { return (int)fTestFont->fCharCodesCount; }